recently ive been spending alot of time on lastfm. this site enables you to get a biasic profile of bands/musicians you may already know and find lots of other artists who write similar music. its quite simple to use, and covers all genres and every artist i know of (infact i spent hours trying to think of an atrist that wasnt registered on lastfm) anyway, in the top right hand corner you will find a search bar, just type an artist in (this also works for songs and albums) and away you go. the first thing you will see once you have clicked "go" is a basic profile of your selected artist. if you scroll down you will find a row of similar artists. if you want you can click "see more". selecting the listed artists will take you to their profile page where you can now suss. them out.
creating an account on lasfm enables you to comment on artists/songs/albums and listen to "lastfm radio" for only $3.00 a month (you might only want to pay if your going to use this frequently) however you wont really need an acount, i dont use mine often.
however i would say that lastfm is certainly worth checking out, its better than reading through magazines for hours looking for new music. just click here to check it out now.